This invention relates to utility standards having decorative bases, such as area lighting posts, and more particularly relates to a modular structural utility standard assembly with decorative wrap-around base covers.
Presently, utility standards are manufactured with shafts welded to large, heavy decorative but structural base castings. These assemblies are costly, non-modular, and are often damaged in shipping. Additionally, they have weaknesses inherent to their design.
It is well known that the heat associated with welding weakens material at the heat-affected zone. Thus, post-bases, posts, or the welds themselves often fail at the heat-affected zone.
Access to electrical wiring is necessary for installation and maintenance of electrical equipment supported by utility standards, and is typically accomplished by cutting a hole, called a hand-hole, into the shaft near the base. Thus, the shaft is structurally weakened at this point of the shaft.
The geometry of aesthetically-pleasing base castings is generally not shaped as necessary for maximizing strength. Sharp corners and decorative indentations, while architecturally stylish, create structural weaknesses and failure points.
An additional disadvantage to utility standards of the present art is that bases having various shaped and sized post openings are required to accommodate shafts of different shapes and sizes. Such varying shafts are required for various strength and appearance purposes. Common shapes and sizes include posts with circular, polygonal, or fluted cross-sections from 3 to 5 inches across. Thus, there is no interchangeability between posts and bases having differing sizes and shapes.
One present attempt to address these problems involves threading a shaft and post base. However, it is readily apparent that such a design is difficult to install. Further, each different size of shaft continues to require a different base, and only cylindrical shafts can be used.
Another attempt to address the problems is described in U.S. Pat. No. 5,499,885 to Chapman. Chapman discloses a method and apparatus for joining a tubular component to another component, such as a base plate, without welding through the use of a joining device nested inside of the passageway, which is then expanded to engage the wall of the passageway. This device, however, involves numerous components, is difficult to assemble in the field, and still lacks easy wiring access.